The present invention relates to a radiological imaging apparatus and detector unit thereof.
A radiological imaging apparatus such as a positron emission tomography (hereinafter referred to as “PET apparatus”) for diagnosing an examinee by detecting radiation emitted from the examinee given radioisotope and laid on an examining table using detectors arranged around the examinee is known.
The PET apparatus is an apparatus which administers radioisotope to an examinee, detects γ-rays emitted from within the body of this examinee using γ-ray detectors arranged around the examinee and outputs a two-dimensional or three-dimensional image of the examinee (e.g., see JP-A-2003-185750 (paragraph 0002, FIG. 12)).
In a nuclear medicine diagnosis using such a radiological imaging apparatus, a diagnosis is conducted by obtaining a two-dimensional or three-dimensional image of the examinee. For this purpose, it is important to obtain a two-dimensional or three-dimensional image with high resolution using the radiological imaging apparatus and to attain this object, for example, hundred thousand (hundred thousand channels) or more detectors are used for the radiological imaging apparatus. Furthermore, since detailed diagnoses are often conducted using a slice image in the direction of the body axis of the examinee, it is important to obtain a slice image with high resolution. To attain this object, it is necessary to arrange many detectors in a close-packed manner and a close-packed arrangement in the circumferential direction is particularly important. On the other hand, when many detectors are used, maintenance thereof may become difficult.
However, conventionally there have not been enough studies on a structure which would satisfy both a structure of equipment for obtaining an image with high resolution and a structure of equipment for making maintenance easier.
It is an object of the present invention to provide a radiological imaging apparatus and detector unit thereof capable of facilitating replacement of radiation detectors and improving an arrangement density of radiation detectors.